Traces the rise of the primates. Examines the anatomical changes, the beginnings of sociality and speech, the more complex brain, the semi - erect posture and other human - like characteristics.
Describes the early crystal set, and the invention of the valve and its development up to recent times. Explains how the germanium diode and the transistor function, and includes details concerning the crystal lattice, "p" and "n" type germanium, and hole conduction. Discusses some of the present applications of the transistor and its advantages over the thermionic v